[PATCH 5.10 203/406] media: v4l2-core: Fix a potential resource leak in v4l2_fwnode_parse_link()

Greg Kroah-Hartman
2023-09-17T19:31:38Z

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

[ Upstream commit d7b13edd4cb4bfa335b6008ab867ac28582d3e5c ]

If fwnode_graph_get_remote_endpoint() fails, 'fwnode' is known to be NULL,
so fwnode_handle_put() is a no-op.

Release the reference taken from a previous fwnode_graph_get_port_parent()
call instead.

Also handle fwnode_graph_get_port_parent() failures.

In order to fix these issues, add an error handling path to the function
and the needed gotos.

Fixes: ca50c197bd96 ("[media] v4l: fwnode: Support generic fwnode for parsing standardised properties")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/v4l2-core/v4l2-fwnode.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c
index dfc53d11053fc..1977ce0195fee 100644
--- a/drivers/media/v4l2-core/v4l2-fwnode.c
+++ b/drivers/media/v4l2-core/v4l2-fwnode.c
@@ -572,19 +572,29 @@ int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
link->local_id = fwep.id;
link->local_port = fwep.port;
link->local_node = fwnode_graph_get_port_parent(fwnode);
+ if (!link->local_node)
+ return -ENOLINK;

fwnode = fwnode_graph_get_remote_endpoint(fwnode);
- if (!fwnode) {
- fwnode_handle_put(fwnode);
- return -ENOLINK;
- }
+ if (!fwnode)
+ goto err_put_local_node;

fwnode_graph_parse_endpoint(fwnode, &fwep);
link->remote_id = fwep.id;
link->remote_port = fwep.port;
link->remote_node = fwnode_graph_get_port_parent(fwnode);
+ if (!link->remote_node)
+ goto err_put_remote_endpoint;

return 0;
+
+err_put_remote_endpoint:
+ fwnode_handle_put(fwnode);
+
+err_put_local_node:
+ fwnode_handle_put(link->local_node);
+
+ return -ENOLINK;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);

--
2.40.1